“If I buy a home with a view, would my neighbor be allowed to build up or grow their trees and block the view?”
To my knowledge, there’s NO universal law or statute preventing someone from blocking someone else’s view.
All I know of that may protect a view are neighborhood CC&Rs (covenants, conditions, and restrictions) or a deed restriction.
Some neighborhoods (and all condo complexes) have CC&Rs. CC&Rs may contain a provision preventing second story or other additions, limiting tree heights, or protecting views. Be careful because some CC&Rs are not enforceable, for various reasons. (See a real estate attorney.)
A deed restriction could limit the height of any structure or tree, or explicitly protect a view. Years ago I sold a home in P.B. where the neighbors bought it solely so they could record such a deed restriction to protect their view, then resell the house.
Other factors could limit a neighbor’s ability to add another story, such as having already maxed out the allowed square-footage on the lot. Or many parts of the county have a 30-foot height limit, so this may also prevent another story.
So when you buy a San Diego home, if the view is important to you, check out all these factors…